vivarium vs terrarium

vivarium and terrarium both are nouns.

Word	Noun	Adjective	Verb	Adverb
vivarium	Yes	No	No	No
terrarium	Yes	No	No	No

As nouns, terrarium is a hyponym of vivarium; that is, terrarium is a word with a more specific, narrower meaning than vivarium:

vivarium: an indoor enclosure for keeping and raising living animals and plants and observing them under natural conditions
terrarium: a vivarium in which selected living plants are kept and observed

Other hyponyms of vivarium include aquarium, fish tank, marine museum.

vivarium (noun)	terrarium (noun)
an indoor enclosure for keeping and raising living animals and plants and observing them under natural conditions	a vivarium in which selected living plants are kept and observed